The red text effect says "En Fuego!" in Borderlands 3.

"En Fuego!" is a red text modifier on weapons in Borderlands 3

Artifact

Granted Effects

  • 100% incendiary chance for melee attacks, sliding and ground slams.

Can have 2 of the Following

  • Increased Incendiary Resistance.
  • Increased Incendiary Damage
  • Increased Melee Damage

Reference